import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNextLine()) {
            String line = in.nextLine();
//            if (Character.isLowerCase(line.charAt(0))) {
            //这种写法是输出一个，输入一个字符串的话，无法整体将其转换为小写的
                if (line.charAt(0) >= 97 && line.charAt(0) <= 122){//判断是否为小写
                char c = (char) (line.charAt(0) - 32);
                System.out.println(c);
            } else {
                char c = (char) (line.charAt(0) + 32);
                System.out.println(c);
            }
        }
    }
}
